\\[-1.8ex] Soil Heterogeneity & $-$0.049$^{***}$ & $-$0.030$^{***}$ & $-$0.031$^{***}$ & $-$0.031$^{***}$ & $-$0.031$^{***}$ & $-$0.034$^{***}$ \\ 
  & (0.012) & (0.011) & (0.011) & (0.011) & (0.011) & (0.011) \\ 
  & & & & & & \\ 
\\[-1.8ex] 
Observations & 393,016 & 393,016 & 393,016 & 393,016 & 392,967 & 392,967 \\ 
R$^{2}$ & 0.045 & 0.046 & 0.046 & 0.046 & 0.046 & 0.051 \\ 
